How to achieve better training results in less time with interval training

Interval training is one of the most effective methods for improving endurance, speed, and fat burning. In contrast to steady-state endurance training, it is characterized by alternating between high-intensity periods of exertion and short recovery phases. This form of training is used in many sports and offers numerous benefits. But how exactly does interval training work, what variations are there, and how does it compare to classic Zone 2 training? In this article, we dive into everything you need to know about this performance-enhancing training method.

What is interval training

Interval training describes a training method in which short, intense phases of exertion alternate with active or passive recovery phases. Depending on the training goal, the exertion can consist of sprints, strength exercises, or functional movements. The idea behind it is to push the body to its performance limit during the intense phases and allow only incomplete regeneration during the recovery phases. This places maximum demand on the cardiovascular system and trains the muscles efficiently.

What are the principles of interval training

Intensity: The exertion phases are often between 80–100% of the maximum heart rate.

Duration: The length of the exertion intervals varies from a few seconds to several minutes.

Recovery phases: Can be active (slow walking, light jogging) or passive (standing, sitting).

Total duration: Usually between 15 and 40 minutes, depending on intensity and goal.

What are the benefits of interval training

Interval training offers numerous advantages that make it attractive for both amateur and professional athletes:

Increase in endurance and performance: Through repeated high exertion, the body improves its maximal oxygen uptake (VO₂max), which directly translates into better endurance performance. Interval training is particularly important for sports that require short, explosive power output.

Increased fat burning: Interval training boosts fat burning not only during the workout but also afterwards. This afterburn effect (EPOC – Excess Post-Exercise Oxygen Consumption) ensures that the body continues to burn calories for up to 24 hours after the training session.

Time efficiency: Those who are short on time benefit particularly from interval training. A 20–30-minute high-intensity workout can have similar or even better effects than an hour of classic endurance training.

Maintenance and building of muscle mass: While classic endurance training is often associated with muscle loss, interval training can help maintain or even build muscle due to its high intensity. 

Variety and fun: Interval training is extremely versatile and can be constantly redesigned through different exercises and structures. Ideal for avoiding boredom.

What variants of interval training are there

Depending on the training goal, there are various forms of interval training. Methods for running and CrossFit are particularly popular.

Interval training for running

•       Classic running intervals: Example: 8 × 400 m with a 90-second jogging recovery.
• Fartlek training: Spontaneous tempo changes, e.g., sprint to the next lamppost, then slow jog.
• Hill sprints: 6 × 100 m sprint uphill, slow walk back as recovery.
• Sprint intervals: 10 × 30 seconds full-out sprint, 60 seconds walking recovery.

Interval training for CrossFit

•       EMOM: E.g., every minute 10 burpees and 15 air squats for 10 minutes.
• AMRAP: 10 minutes of as many rounds as possible of: 10 kettlebell swings, 10 box jumps, 10 pull-ups.
• Tabata: 20 seconds of exertion, 10 seconds of rest, 8 rounds (e.g., burpees, squats, kettlebell swings).
• Run-strength combination: 400 m sprint + 20 wall balls + 10 deadlifts for 4 rounds.

Interval training vs. Zone 2 training

Zone 2 training refers to steady, moderate endurance training at 60–70% of the maximum heart rate. It serves to build basic endurance and fat burning but is much less intense than interval training.

Interval training:

• Promotes speed, muscular endurance, and maximal oxygen uptake.
• High intensity (80–100% HRmax) with short recovery phases.
• Short duration (15–40 minutes) with high calorie burning due to the afterburn effect.
• High need for recovery, as it places heavy stress on the nervous system.
• Supports muscle growth and maintenance.

Zone 2 training:

•       Improves basic endurance and fat metabolism.
• Low to moderate intensity (60–70% HRmax), steady exertion.
• Long duration (45–120 minutes).
• Rapid recovery, can be performed daily.
• Little influence on muscle growth, but good for general fitness.
• Can also be used as active recovery.

When is which method better

Interval training is suitable for:

• Rapid performance improvement.
• Time-efficient workouts.
• Explosive sports (CrossFit, sprint, martial arts).
• Fat burning with afterburn effect.

Zone 2 training is suitable for:

• Long-term basic endurance.
• Recovery between intense training days.
• Health and wellness goals.
• Improvement of fat metabolism         

Conclusion

Interval training is an extremely effective method for quickly improving strength, endurance, and fat burning. It offers many benefits but is also more demanding than classic Zone 2 training. Both methods have their place, and the best strategy often involves combining both approaches. While interval training provides speed and performance gains, Zone 2 training helps to sustainably improve basic endurance. Depending on the training goal and time budget, the right mix of both methods can lead to optimal results.